透水铺装去除污染效能及清洗特性研究

Experimental study on pollution efficiency and cleaning characteristics of permeable pavement

针对透水铺装对雨水径流污染的缓解作用,采用模拟降雨试验研究了透水铺装的污染物去除效能及影响因素,并采用超纯水对透水铺装进行清洗,探究清洗出水的水质特性和透水铺装的污染状况。结果表明,透水铺装对SS、TP和Zn的去除效能非常高,平均去除率分别可达98.15%、97.33%和97.58%,NH3-N和COD的去除效果相对较差,平均去除率分别为20.87%和3.52%;径流雨水中污染物的初始浓度对去除效能的影响不大,而降雨强度的影响相对较大,尤其对于去除率相对较低的污染物,当降雨重现期由1年增至100年时,NH3-N和COD的平均去除率分别降低了8.68%和44.23%;在对透水铺装进行清洗时发现,清洗出水呈碱性,被截留和残留在透水铺装结构层内的COD和NH3-N易被水流冲出,而SS、TP和Zn不易随水流冲出,可见透水铺装易受颗粒物的堵塞。

For the mitigation effect of permeable pavement on stormwater runoff pollution,simulated rainfall experiment was used to study the pollutant removal efficiency and influencing factors of permeable pavement.The ultra-pure water was used to clean the permeable pavement and the water quality characteristics of the rinsing water and the pollution status of the permeable pavement were studied.The results show that the effluent pavement have very high removal efficiency of SS,TP and Zn.The average removal rate can reach 98.15%,97.33%and 97.58%respectively.The removal efficiency of NH3-N and COD is relatively poor,with average removal rates of 20.87%and 3.52%,respectively.The initial concentration of pollutants in runoff rainwater has little effect on the removal efficiency,but the impact of rainfall intensity is relatively large,especially for pollutants with relatively low removal rates.When the return period of rainfall increases from one year to 100 years,the average removal rates of NH3-N and decreased by 8.68%and 44.23%respectively.When cleaning the permeable pavement,it is found that the rinsing water is alkaline.The COD and NH3-N remaining in the permeable pavement structure layer are easily washed out by the water flow,while the SS,TP and Zn are not easy to flush with the water flow.It can be seen that the permeable pavement was liable to be blocked by the particulate matter.